Gentlemen, somebody's intro thread is hardly the place to have any sort of argument, is it?

The comment was based on the very boxy square format 126 format DSLRs of yore. Zeiss Ikon and Rollei made examples.

All the Pentax macro lenses are excellent lenses and this one is no exception. Yes, you can use it as a standard 50mm lens as well. The only drawback is the smaller maximum aperture and the higher cost.

In terms of price, there are fewer 50mm macros around than 100mm ones, so eBay will give you a current idea.

What price are you being asked for?

I don't see what's so extraordinary. Accessories are provided for those who need them, that's got nothing to do with how "serious" we are.

The square format has been mooted for many, many years, but when tried on film SLRs has always failed.

If you want a square image, then crop square. For the right shot it can be perfect, but in this widescreen world it wouldn't stand a chance if that was the normal format.

It's odds on you'd get a square camera that used the shortest side of the APS-C format anyway, but if it was the longest side you'd end up with a very odd looking beast with little general appeal.

I think so too. The higher grade Pentax lenses are fine, even some other make zooms are fine, but it's a hit and miss affair unless we're talking about the very best lenses.

I've tried many grips on many cameras and have never found any point to adding to the weight and bulk.

The Pentax cameras are compact and efficient so no need IMHO to add anything.

As for batteries, I carry three (including the one in the camera) and rotate them. Battery life is never an issue.

Having said that, if anyone finds a grip useful, for any reason, then go for it.

The 100mm macro lenses are equivalent to using a 150mm on film, so they are already longer in that sense.

There was a Pentax 200mm macro and there may well be other 180mm/200mm macros around, perhaps Zeiss? However, we are talking big money for these.

How close do you need to be and with live or still specimens?

A Weston Master V or Euro-Master might be more useful to you, if you can find a good one at a reasonable price.

Not a great light meter to be honest. I'd have to handle it to be sure what turns what, but in any event your camera meter will no doubt give more accurate results.

I'm not sure privelidged is the word I'd use, but if you like what the end result is that's enough.